# 2.13.5. V4L2_META_FMT_VSP1_HGO (‘VSPH’)¶

Renesas R-Car VSP1 1-D Histogram Data

## 2.13.5.1. Description¶

This format describes histogram data generated by the Renesas R-Car VSP1 1-D Histogram (HGO) engine.

The VSP1 HGO is a histogram computation engine that can operate on RGB, YCrCb or HSV data. It operates on a possibly cropped and subsampled input image and computes the minimum, maximum and sum of all pixels as well as per-channel histograms.

The HGO can compute histograms independently per channel, on the maximum of the three channels (RGB data only) or on the Y channel only (YCbCr only). It can additionally output the histogram with 64 or 256 bins, resulting in four possible modes of operation.

In

*64 bins normal mode*, the HGO operates on the three channels independently to compute three 64-bins histograms. RGB, YCbCr and HSV image formats are supported.In

*64 bins maximum mode*, the HGO operates on the maximum of the (R, G, B) channels to compute a single 64-bins histogram. Only the RGB image format is supported.In

*256 bins normal mode*, the HGO operates on the Y channel to compute a single 256-bins histogram. Only the YCbCr image format is supported.In

*256 bins maximum mode*, the HGO operates on the maximum of the (R, G, B) channels to compute a single 256-bins histogram. Only the RGB image format is supported.

**Byte Order.**
All data is stored in memory in little endian format. Each cell in the tables
contains one byte.

Offset |
Memory |
||||
---|---|---|---|---|---|

[31:24] |
[23:16] |
[15:8] |
[7:0] |
||

0 |
R/Cr/H max [7:0] |
R/Cr/H min [7:0] |
|||

4 |
G/Y/S max [7:0] |
G/Y/S min [7:0] |
|||

8 |
B/Cb/V max [7:0] |
B/Cb/V min [7:0] |
|||

12 |
R/Cr/H sum [31:0] |
||||

16 |
G/Y/S sum [31:0] |
||||

20 |
B/Cb/V sum [31:0] |
||||

24 |
R/Cr/H bin 0 [31:0] |
||||

… |
|||||

276 |
R/Cr/H bin 63 [31:0] |
||||

280 |
G/Y/S bin 0 [31:0] |
||||

… |
|||||

532 |
G/Y/S bin 63 [31:0] |
||||

536 |
B/Cb/V bin 0 [31:0] |
||||

… |
|||||

788 |
B/Cb/V bin 63 [31:0] |

Offset |
Memory |
||||
---|---|---|---|---|---|

[31:24] |
[23:16] |
[15:8] |
[7:0] |
||

0 |
max(R,G,B) max [7:0] |
max(R,G,B) min [7:0] |
|||

4 |
max(R,G,B) sum [31:0] |
||||

8 |
max(R,G,B) bin 0 [31:0] |
||||

… |
|||||

260 |
max(R,G,B) bin 63 [31:0] |

Offset |
Memory |
||||
---|---|---|---|---|---|

[31:24] |
[23:16] |
[15:8] |
[7:0] |
||

0 |
Y max [7:0] |
Y min [7:0] |
|||

4 |
Y sum [31:0] |
||||

8 |
Y bin 0 [31:0] |
||||

… |
|||||

1028 |
Y bin 255 [31:0] |

Offset |
Memory |
||||
---|---|---|---|---|---|

[31:24] |
[23:16] |
[15:8] |
[7:0] |
||

0 |
max(R,G,B) max [7:0] |
max(R,G,B) min [7:0] |
|||

4 |
max(R,G,B) sum [31:0] |
||||

8 |
max(R,G,B) bin 0 [31:0] |
||||

… |
|||||

1028 |
max(R,G,B) bin 255 [31:0] |